I believe Wifeyb asked this question not long ago. Try a search.
I'd go with a passport holder or pencil/long cosmetic pouch
I just bought the Poppy Demi Clutch Wristlet
I had something flat that had compartments and I wanted something from Coach so I bought this to try. It has compartments which I like for receipts in one, coupons in another and holds cards that I don't want bulking up my main wallet. It's a little thicker than what I was using but I think it will work well.
I linked an ebay auction since I didn't have a picture handy...(have no idea who the seller is...just wanted the pic)